Toothed belts generally comprise a body made of elastomeric material, in which is embedded a plurality of longitudinal filiform resistant inserts, also referred to as “cords”, and a plurality of teeth coated with a coating fabric.
Each component of the belt contributes to increase the performance in terms of mechanical resistance, so as to reduce the risk of failure of the belt and to increase the specific transmissible power.
The coating fabric of the belts increases the resistance to abrasion and hence protects the working surface of the belt from wear that is due to the rubbing between the flanks and cavities of the teeth of the belt and the flanks and the cavities of the grooves of the pulley with which the belt interacts.
In addition, the coating fabric decreases the coefficient of friction on the working surface, reduces the deformability of the teeth and above all reinforces the root of the tooth, thus preventing the tooth shear.
The coating fabric used can be formed by a single layer or, alternatively, can be double-layered so as to guarantee a greater strength and greater rigidity. The fabric is normally treated with a compound designed to increase the adherence between the body and the fabric itself.
The cords contribute to ensure the necessary mechanical characteristics of the belt and contribute essentially to the modulus of the belt itself and in particular thus ensure maintenance of performance of the belt over time. The cords are generally formed by twisting fibres with high modulus a number of times.
Also the cords are normally treated with compounds designed to increase the compatibility of the fibres with the body mixture that surrounds the cords themselves.
For example, the cords can be treated with elastomeric latexes that function as “adhesives”.
Finally, the body mixture enables connection of the various aforesaid elements and must present adequate hardness and ensure that the various elements constituting the belt itself contribute synergistically to the final performance of the belt itself.
The body mixtures have a base of one or more elastomeric materials eventually enriched with fibres to increase their hardness.
In order to be able to improve the lifetime and the performance of the belts there is a continuous search for new solutions to enable an increase in the chemico-physical compatibility between the various materials that constitute the basic elements of the belts. For this purpose, there is, for example, the search for new treatments for the cords and new treatments for the coating fabric of the teeth that will enable an increase in the compatibility between the fabric, the cords, and the body.